Methods for passing multiple sutures through tissue

ABSTRACT

Methods for passing multiple sutures through tissue are provided herein. In particular, the methods described herein allow multiple sutures to be passed through tissue without removing a suture passing instrument from a patient&#39;s body. In one embodiment, a method for passing a suture through tissue is provided that includes loading first and second suture limbs into a suture passing instrument, positioning the instrument within a patient&#39;s body, actuating the instrument to pass a portion of the first suture limb through the tissue, pulling the first suture limb through the tissue, pulling the second suture limb to reload the suture passing instrument without removing the instrument from the patient&#39;s body, actuating the instrument a second time to pass a portion of the second suture limb through the tissue, and pulling the second suture limb through the tissue.

FIELD

This application relates generally to surgical procedures and, moreparticularly, to methods for passing multiple sutures through tissueduring a surgical procedure.

BACKGROUND

Many surgical procedures require fixing tissue with respect to bone,artificial anchors, or other tissue using sutures. A variety of stitchesare known that can be utilized to position and fix a portion of tissueat a desired location. However, passing sutures through tissue to createone or more stitches can be challenging due to the confined workingspace of a patient's body and the limited accessibility of the tissue.This is especially true in minimally invasive surgical procedures thatrequire surgical tools to be inserted into a patient's body throughsmall diameter cannulas, thereby preventing a user from directlymanipulating a suture or tissue.

Several suture passing instruments have been developed in response tothese and other challenges that allow a user to grasp a portion oftissue and pass a suture through the grasped tissue. The portion of thesuture passed through the tissue can then be grasped with a second tooland further manipulated. One example of a suture passing instrument isdescribed in U.S. Pat. No. 7,879,046 to Weinert et al., entitled“Suturing Apparatus and Method,” the contents of which are herebyincorporated by reference in their entirety. A number of other suturepassing instruments are also known in the art.

One challenge faced by users of suture passing instruments is the needto repeatedly remove the instrument from a patient's body for reloading.As mentioned above, a variety of stitches are known that can be used inpositioning and fixing tissue, and most stitches require passingmultiple portions of one or more suture strands through tissue at one ormore locations. Using known devices and methods, a user loads a singlesuture into a suture passing instrument, inserts and positions theinstrument within a patient's body, passes the suture through tissue,and removes the instrument from the patient's body to repeat these stepsfor each additional suture that must be passed through tissue.

The repeated insertion and removal of the suture passing instrument fromthe patient's body can introduce a number of challenges. For example,sutures passed through tissue often have a free end extending throughthe cannula used to insert the suture passing instrument so that a usercan further manipulate the suture during the procedure. Repeatedlyremoving the suture passing instrument and reintroducing it through thecannula can risk snagging or entangling the instrument with one or moreof the suture free ends extending through the cannula. Furthermore,removing and reintroducing the suture passing instrument can distort auser's frame of reference for creating a stitching pattern because theinstrument must be positioned anew for each suture passing. Stillfurther, in some procedures it can be desirable to pass multiple suturesthrough a single hole in tissue. It is difficult to reposition thesuture passing instrument after removing it from the body for reloadingsuch that a second suture can be passed through the same hole as a firstsuture. These challenges add time and difficulty to surgical proceduresthat require passing multiple sutures through tissue.

Accordingly, there is a need for novel methods for passing multiplesutures through tissue in a more efficient manner. In particular, thereis a need for improved methods for loading and utilizing existing suturepassing instruments to pass multiple sutures through tissue and reducethe challenges associated with repeatedly inserting and removing asuture passing instrument from a patient's body.

SUMMARY

The present invention generally provides methods for passing multiplesutures through tissue. In particular, the methods described herein passmultiple sutures through tissue without having to remove a suturepassing instrument from a patient's body to reload the instrument. Themethods described herein can utilize existing suture passing instrumentsand address several challenges encountered by users of these prior artdevices. For example, the methods described herein double-load a suturepassing instrument with suture limbs that can be opposite ends of asingle strand of suture, or two ends of separate suture strands. Usingthe methods described herein, a user can insert the instrument into apatient's body and pass both suture limbs through tissue without havingto remove the instrument from the patient's body for reloading. To dothis, the methods described herein provide a novel remote reloadingprocess accomplished by manipulating a free end of one of the suturelimbs loaded in the instrument. The methods described herein can beutilized to create a number of different stitches in tissue, including,for example, an inverted mattress stitch. Such a stitching pattern canbe useful in a variety of surgical procedures, including, for example,the repair of a rotator cuff tear in a patient's shoulder.

Reducing the number of times that a user removes a suture passinginstrument for reloading can have a number of advantages. These caninclude, for example, reducing the possibility of snagging or entanglingthe suture passing instrument on previously-passed suture strands thatextend through a cannula used to introduce the instrument, reducing thedifficulty level of a procedure, reducing the time required for aprocedure, etc. In addition, by passing multiple sutures withoutremoving the device from a patient's body, a frame of reference can becreated between consecutive suture passes, thereby allowing for moreaccurate and easier repositioning of the suture passing instrument.Still further, the methods described herein allow multiple sutures to bepassed through a single hole formed in tissue, which can be desirable ina number of procedures.

In one aspect, a method of passing a suture through tissue is providedthat includes loading a first suture limb into a retaining mechanismdisposed at a distal end of a suture passing instrument such that thefirst suture limb extends on a first side of the instrument. The firstside of the instrument can be any side or surface but, in someembodiments, can be a bottom surface of the instrument. The methodfurther includes loading a second suture limb into the retainingmechanism of the suture passing instrument such that the second suturelimb extends on the first side of the instrument. The method alsoincludes positioning first and second jaws of the suture passinginstrument to grasp tissue within a patient's body, and deploying aneedle from the suture passing instrument such that the needle extendsthrough the tissue grasped between the first and second jaws of theinstrument. The needle carries a portion of at least the first suturelimb through the tissue such that the first and second suture limbsextend from a first tissue surface and at least a first suture loop isformed on a second tissue surface opposite the first tissue surface. Themethod further includes pulling the first suture loop to draw the firstsuture limb through the tissue, and pulling the second suture limbtoward a proximal end of the suture passing instrument to draw thesecond suture limb into a proximal end of the retaining mechanismwithout removing the suture passing instrument from the patient's body.The method also includes deploying the needle from the suture passinginstrument a second time to carry a portion of the second suture limbthrough the tissue such that the second suture limb extends from thefirst tissue surface and a second suture loop is formed on the secondtissue surface, and pulling the second suture loop to draw the secondsuture limb through the tissue.

The methods described herein can include a number of additional steps orvariations that are considered within the scope of the presentinvention. For example, in some embodiments, the second suture limb canbe loaded into the retaining mechanism such that it can extend outsidethe patient's body when the suture passing instrument is inserted intothe patient's body. This can result in the second suture limb extendingfarther from the suture passing instrument than the first suture limb.By way of further example, in some embodiments that first suture limbcan extend from the suture passing instrument by about 10-20 mm and thesecond suture limb can extend from the suture passing instrument byabout 250 mm.

In certain embodiments, positioning the first and second jaws of thesuture passing instrument can include inserting the instrument into apatient's body, opening the jaws to receive tissue therebetween, andclosing the jaws to grasp the tissue. Furthermore, in some embodiments,the instrument can be inserted into the patient's body through acannula.

In other embodiments, the method can further include retracting theneedle following deployment such that the needle retracts into thesuture passing instrument without moving the first or second suturelimbs. The retraction of the needle can ensure that the needle does notdamage adjacent tissue and also leaves the one or more suture loopsformed on the second tissue surface more accessible to be grasped andmanipulated.

In still other embodiments, the method can further include, prior topulling the first suture loop, determining which of two suture loops isthe first suture loop by pulling the second suture limb toward aproximal end of the suture passing instrument to reduce the size of asecond suture loop formed on the second tissue surface. In particular,pulling on the second suture limb can reduce the size of one of the twosuture loops formed on the second tissue surface, thereby allowing auser to differentiate between the first and second suture loops.

In some embodiments, the method can further include at least partiallyopening the first and second jaws prior to pulling the second suturelimb toward a proximal end of the instrument to permit easier movementof the second suture limb with respect to the retaining mechanism.Opening the jaws can reduce the amount of force necessary to pull thesecond suture limb into the proximal-most portion of the retainingmechanism. Seating the second suture limb without opening the jaws ispossible as well, however. In addition, in some embodiments the jaws canbe only partially opened such that the second suture limb can move moreeasily, but the tissue can still be relatively firmly grasped by thefirst and second jaws such that the suture passing instrument does notmove with respect to the tissue.

In certain embodiments, the method can further include repositioning thesuture passing instrument without removing the instrument from thepatient's body before deploying the needle a second time such that thesecond suture limb is passed through tissue at a different location thanthe first suture limb. Repositioning the suture passing instrumentbetween each deployment of the needle can permit the creation of, forexample, an inverted mattress stitch in the tissue. In some embodiments,repositioning the suture passing instrument can include opening thefirst and second jaws to release the tissue grasped therebetween, movingthe instrument to receive a different portion of tissue between thefirst and second jaws, and closing the first and second jaws to graspthe different portion of tissue therebetween.

In some embodiments, however, the suture passing instrument may not berepositioned between the first and second deployments of the needle suchthat both the first and second suture limbs extend through a single holeformed in the tissue. Passing multiple suture limbs through a singlehole in tissue can be utilized, for example, in combination with a helixbone anchor and/or spanning techniques across bone anchors used forrotator cuff repair.

In other embodiments, the method can further include attaching thesecond suture limb to a tensioning device that is coupled to the suturepassing instrument at a location proximal to the retaining mechanism.The tensioning device can be configured to pull the second suture limbtoward a proximal end of the instrument. Attaching the second suturelimb to such a tensioning device can avoid the need to provide a longersecond suture limb that can be manipulated by a user directly during asurgical procedure.

The methods described provide a great deal of utility and can be used ina variety of manners. For example, in some embodiments the method canfurther include attaching the first and second suture limbs to a boneanchor. This attachment can be performed before or after the suturelimbs are passed through tissue. Further, in certain embodiments, thefirst and second suture limbs can be opposite ends of a single suturestrand. Loading both ends of a single suture strand can create, forexample, an inverted mattress stitch in tissue without removing thedevice from the patient's body. After forming the stitch, the free endsof the suture strand can be further manipulated (e.g., tied off to otherstrands, affixed to a bone anchor, etc.) and trimmed at the end of aprocedure. In still other embodiments, the first and second suture limbscan be ends of separate suture strands, and the method can furtherinclude repeating the steps of the method recited above using theopposite ends of the separate suture strands as the first and secondsuture limbs. Utilizing the ends of separate suture strands as the firstand second suture limbs, and repeating the method with the other ends ofthe separate strands, can create, for example, a double-width invertedmattress stitch in tissue with only one removal and reintroduction ofthe suture passing instrument.

In another aspect, a method of passing a suture through tissue isprovided that includes loading first and second suture limbs into aretaining mechanism of a suture passing instrument such that the firstand second suture limbs extend from a first side of the instrument, andinserting the suture passing instrument into the body of a patient. Themethod further includes positioning first and second jaws of the suturepassing instrument to grasp tissue therebetween, and actuating thesuture passing instrument to pass a portion of at least the first suturelimb through the tissue grasped between the first and second jaws suchthat the first and second suture limbs extend from a first tissuesurface and at least a first suture loop is formed on a second, oppositetissue surface. The method also includes pulling the first suture loopto draw the first suture limb through the tissue, and pulling the secondsuture limb toward a proximal end of the suture passing instrument todraw the second suture limb into a proximal end of the retainingmechanism without removing the suture passing instrument from thepatient's body. The method further includes actuating the suture passinginstrument a second time to pass a portion of the second suture limbthrough the tissue grasped between the first and second jaws such thatthe second suture limb extends from the first tissue surface and asecond suture loop is formed on the second tissue surface, and pullingon the second suture loop to draw the second suture limb through thetissue.

In certain embodiments, the method can further include, prior to pullingthe first suture loop, determining which of two suture loops is thefirst suture loop by pulling the second suture limb toward a proximalend of the suture passing instrument to reduce the size of a secondsuture loop formed on the second tissue surface.

In other embodiments, the method can further include repositioning thesuture passing instrument without removing the instrument from thepatient's body before actuating the instrument a second time such thatthe second limb is passed through tissue at a different location fromthe first suture limb.

Furthermore, in certain embodiments, the first and second suture limbscan be ends of separate suture strands, and the method can furtherinclude removing the instrument from the patient's body and repeatingthe method using the opposite ends of the separate suture strands as thefirst and second suture limbs.

In another aspect, a method for repairing a tear in tissue is providedthat includes loading a first suture limb into a retaining mechanismdisposed at a distal end of a suture passing instrument, the firstsuture limb having a free end and an opposite end anchored to bonewithin a patient's body. The method further includes loading a secondsuture limb into the retaining mechanism of the suture passinginstrument, the second suture limb having a free end and an opposite endanchored to bone within a patient's body. The method also includespositioning first and second jaws of the suture passing instrument tograsp tissue within the patient's body, and actuating the suture passinginstrument to pass a portion of the first suture limb through the tissuegrasped between the first and second jaws such that a first suture loopis formed on a surface of the tissue. The method further includespulling the first suture loop to draw the free end of the first suturelimb through the tissue, and pulling the free end of the second suturelimb toward a proximal end of the suture passing instrument to draw thesecond suture limb into a proximal end of the retaining mechanismwithout removing the suture passing instrument from the patient's body.The method also includes actuating the suture passing instrument asecond time to pass a portion of the second suture limb through thetissue grasped between the first and second jaws such that a secondsuture loop is formed on the surface of the tissue. The method furtherincludes pulling on the second suture loop to draw the free end of thesecond suture limb through the tissue, and anchoring the free ends ofthe first and second suture limbs to bone to secure the tissue withrespect to the bone.

The method can have a number of variations or additional steps. In someembodiments, for example, anchoring the free ends of the first andsecond suture limbs to bone can include securing the free end of thefirst suture limb to a first bone anchor and the free end of the secondsuture limb to a second bone anchor. In other embodiments, the methodcan further include repositioning the suture passing instrument prior toactuating the suture passing instrument a second time. Repositioning thesuture passing instrument in this manner can pass the free ends of thefirst and second suture limbs through the tissue at two differentlocations. In still other embodiments, the suture passing instrumentneed not be repositioned such that the free ends of the first and secondsuture limbs are passed through the tissue at a single location.

In certain embodiments, the method can also include repeating the stepsof loading, positioning, and actuating the suture passing instrumentwith a third and a fourth suture limb that are also anchored at one endto bone in a patient's body. In such an embodiment, the method can alsoinclude anchoring the free ends of the third and fourth suture limbs tobone to secure the tissue with respect to the bone.

The method can be particularly suited to use in repairing tears in apatient's rotator cuff. In particular, the method can be used to spanthe first and second suture limbs through tissue and between a pluralityof bone anchors. Accordingly, in certain embodiments, the tissue can berotator cuff tissue and the bone can be the humerus.

BRIEF DESCRIPTION OF THE DRAWINGS

The aspects and embodiments of the invention described above will bemore fully understood from the following detailed description taken inconjunction with the accompanying drawings, in which:

FIG. 1 is an illustration of one embodiment of a suture passinginstrument;

FIG. 2 is an exploded view illustration of an elongate shaft and lowerjaw of the suture passing instrument of FIG. 1;

FIG. 3 is a detailed view illustration of the lower jaw of the suturepassing instrument of FIG. 1;

FIG. 4 is an illustration of the lower jaw of the suture passinginstrument of FIG. 1 as assembled;

FIG. 5 is an illustration of one embodiment of a first suture limbloaded into a retaining mechanism of a suture passing instrument;

FIG. 6 is an illustration of one embodiment of a second suture limbloaded into the retaining mechanism of the suture passing instrument ofFIG. 5;

FIG. 7 is a top view illustration of the first and second suture limbsloaded into the retaining mechanism of the suture passing instrument ofFIG. 5;

FIG. 8 is an illustration of a second suture limb drawn toward aproximal end of the suture passing instrument of FIG. 5;

FIG. 9 is an illustration of one embodiment of a suture passinginstrument being inserted into a patient's body;

FIG. 10 is an illustration of one embodiment of a needle passing throughtissue and carrying portions of first and second suture limbs throughthe tissue;

FIG. 11 is an illustration of first and second suture loops formed on atissue surface after the needle of FIG. 10 is retracted into the suturepassing instrument;

FIG. 12 is an illustration of one embodiment of determining which of twosuture loops is a first suture loop by pulling a second suture limbtoward a proximal end of a suture passing instrument;

FIG. 13 is an illustration of one embodiment of a second suture limbpulled toward a proximal end of a suture passing instrument until asingle suture loop remains on a tissue surface;

FIG. 14 is an illustration of one embodiment of a suture graspermanipulating a suture loop passed through tissue by a suture passinginstrument;

FIG. 15 is an illustration of one embodiment of a first suture limbpulled through tissue;

FIG. 16 is an illustration of one embodiment of a suture passinginstrument reloaded and repositioned in advance of passing a secondsuture limb through tissue;

FIG. 17A is an illustration of two inverted mattress stitches in tissue;

FIG. 17B is an illustration of a double-width inverted mattress stitchin tissue; and

FIGS. 18A-18D illustrate one embodiment of a rotator cuff repairprocedure that can be performed using the suture passing methods of thepresent invention.

DETAILED DESCRIPTION

Certain exemplary embodiments will now be described to provide anoverall understanding of the principles of the methods disclosed herein.One or more examples of these embodiments are illustrated in theaccompanying drawings. Those skilled in the art will understand that themethods specifically described herein and illustrated in theaccompanying drawings are non-limiting exemplary embodiments and thatthe scope of the present invention is defined solely by the claims. Thefeatures illustrated or described in connection with one exemplaryembodiment may be combined with the features of other embodiments. Suchmodifications and variations are intended to be included within thescope of the present invention.

The present invention is generally directed to methods for passingsutures through tissue within a patient's body. In particular, themethods described herein pass multiple sutures through tissue withouthaving to remove a suture passing instrument from the patient's body toreload the instrument. In one embodiment, this can be accomplished usinga method for double-loading a suture passing instrument in combinationwith a method of remotely reloading the suture passing instrument aftera first suture is passed through tissue. The method of reloading,described in more detail below, can include manipulating a free end of asuture limb loaded into the suture passing instrument from outside thepatient's body.

Reducing the number of times a suture passing instrument is removed fromand reintroduced into a patient's body during a procedure can have anumber of advantages. For example, the overall difficulty of theprocedure and the time required to complete it can be reduced due to areduction in the number of steps required. In addition, the risk ofsnagging or entangling the suture passing instrument onpreviously-passed suture strands that extend through a cannula orpercutaneous portal used to introduce the instrument can be reduced.Furthermore, the instrument can more easily be repositioned betweenconsecutive suture passes, as a user's frame of reference will not belost (i.e., the user will not become disoriented) by having to remove,reload, reintroduce, and reposition the instrument anew before passing asecond suture through tissue. Still further, in some procedures it canbe desirable to pass multiple sutures through a single hole formed intissue (e.g., passing opposite ends of a single suture strand through asingle hole to leave a loop on one side of tissue that can be affixed toan anchor, etc.). However, it is difficult to reposition a suturepassing instrument to utilize a previously formed hole in tissue afterremoving the instrument from the patient's body to reload it. Using themethods described herein, multiple sutures can be passed at a singlelocation without having to withdraw or reposition the instrument betweenpasses.

Another advantage of the methods for passing multiple sutures describedherein is that they can be used in combination with known suture passinginstruments that have previously been configured to pass only a singlesuture before being removed from a patient's body for reloading. FIG. 1illustrates one embodiment of a known suture passing instrument 310. Theinstrument 310 can include a set of first and second jaws 314 at adistal end thereof, and a handle assembly 320 at a proximal end 312 ofthe instrument. The jaws 314 and handle assembly 320 can be connected byan elongate shaft 330, thereby making the instrument suitably shaped forintroduction into a patient's body through, for example, a smalldiameter cannula or percutaneous insertion portal during a minimallyinvasive surgical procedure.

The jaws 314 can include a lower fixed jaw 340 and an upper movable jaw350. The lower fixed jaw 340 can be formed as an integral part of theelongate shaft 330 and can include a retaining mechanism (see FIGS. 2-4)that is configured to retain a portion of a suture loaded therein. Theupper movable jaw 350 can be pivotally coupled to the lower jaw and canalso be coupled to a jaw movement mechanism 360 in the handle assembly320 such that movement of a trigger 361 can cause the movable jaw 350 toopen or close. The movable jaw 350 can include an open portion 355 thatcan surround a protruded portion 357 of the lower jaw 340 when the jaws314 are in a closed configuration.

A suture can be passed through tissue grasped between the jaws 314 usinga bendable needle 400 that can extend from the handle assembly 320 tothe jaws 314. The bendable needle can include a distal tip 404configured to puncture tissue when deployed from the instrument, as wellas a proximal and a distal needle body 401, 403. The needle can alsoinclude a notch 405 formed in a side thereof that can be configured tocatch a suture loaded in the retaining mechanism of the lower jaw 340and carry it through tissue grasped between the jaws 314. A proximal endof the needle 400 can be coupled to a needle movement mechanism 380 suchthat movement of a second trigger 381 can cause the needle 400 to deployfrom the suture passing instrument or retract into the instrument.

FIGS. 2-4 illustrate in more detail the lower jaw 340 and retainingmechanism 410 of the suture passing instrument shown of FIG. 1. Asmentioned above, the lower jaw 340 can include a lower jaw body 341 thatis formed as an integral part of the elongate shaft 330 that couples thejaws 314 to the handle assembly 320. The lower jaw 340 can also includea jaw insert 342 that can be removably or permanently attached to thelower jaw body 341. The jaw insert 342 can be configured to rest onledges 349 formed in the lower jaw body 341 (as shown in FIG. 3) suchthat the lower jaw body and jaw insert can define a needle channel 343therebetween. The bendable needle can be configured to rest within thechannel 343 and advance distally (or retract proximally) through thechannel when deployed by movement of the needle trigger 381. The lowerjaw body 341 and jaw insert 342 can include a sloping distal portionthat can deflect the bendable needle 400 such that it extends from thesuture passing instrument in a direction offset from an elongate axis ofthe instrument. In one embodiment, the offset can be approximately 90degrees, such that the needle 400 extends from the instrument in adirection substantially perpendicular to the elongate axis of theinstrument.

The lower jaw body 341 and jaw insert 342 can also include features thatdefine a retaining mechanism 410 configured to hold a suture loadedtherein before it is passed through tissue disposed between the jaws314. For example, and as shown in FIGS. 3-4, the lower jaw body 341 caninclude a forked distal end 345 that includes a suture-loading ingressprovided as an end slot 346. The end slot 346 can lead to a suture slot347 contained in both the lower jaw body 341 and the jaw insert 342. Thesuture slot 347 can terminate at a proximal end thereof at a sutureretention node or slot end 348 where the suture can be frictionally heldbefore being passed through tissue by the bendable needle 400.

An exemplary prior art method for using the suture passing instrumentshown in FIGS. 1-4 can begin with loading a portion of a suture strandinto the retaining mechanism 410 such that the suture resides at thesuture retention node 348. The suture passing instrument can then beinserted into a patient's body and positioned such that tissue isgrasped between the jaws 314. The needle movement mechanism 380 can thenbe actuated to advance the bendable needle 400 distally. As the needle400 moves toward the distal end of the instrument, the notch 405 formedin a side of the needle can catch the suture residing in the sutureretention node 348 and carry it distally along the suture slot 347. Asthe needle is advanced further, it can extend from the channel exit 344and pass through the tissue grasped between the jaws 314, carrying thesuture with it. After the needle passes entirely through the tissue, itcan be retracted into the instrument, leaving behind a loop of sutureformed on an opposite side of the tissue from the lower jaw 340. Thisloop can be grasped by a hook feature on the suture passing instrument(e.g., hook 1010 shown in FIG. 10) or a second tool and pulled to passthe suture through the tissue.

A more detailed explanation of the suture passing instrument 310 and itsknown method of use can be found in U.S. Pat. No. 7,879,046 to Weinertet al., entitled “Suturing Apparatus and Method,” which is herebyincorporated by reference in its entirety. One of skill in the art willappreciate that the suture passing instrument and retaining mechanismdescribed above are just one of a number of devices and mechanisms knownin the art. For example, in some embodiments a retaining mechanism caninclude a suture slot that is offset 90 degrees from the slot 347 shownin FIG. 7 and configured for loading a suture strand on a side of theinstrument. A number of variations on the exemplary retaining mechanismdescribed above—as well as other retaining mechanism configurations—areknown in the art and the methods described herein need not be limited tothe described embodiment of a suture passing instrument and retainingmechanism.

As noted above, a limitation of the suture passing methods known in theprior art is that only a single suture can be passed through tissuebefore the instrument must be removed from a patient's body and reloadedwith a second suture. Many procedures require passing several suturesthrough tissue at a variety of locations, which can result in severalrepeated cycles of inserting an instrument into a patient, passing asuture, and removing the instrument to reload it. These repeated cyclesadd complexity to a surgical procedure, increase the time required tofinish the procedure, and also run the risk of suture entanglement withsutures that reside in a cannula or portal used to introduce theinstrument into a patient's body. The methods described herein addressthese problems by passing multiple sutures through tissue withoutremoving the suture passing instrument from a patient's body. Inparticular, a method is provided that includes double-loading a suturepassing instrument, such as the instrument 310 described above, suchthat two sutures can be passed through tissue at one or more locationswithout removing the instrument from a patient's body.

In one embodiment, a method of passing multiple sutures can includeloading a first suture limb or portion of suture into a retainingmechanism of a suture passing instrument, as illustrated in FIG. 5. Asshown in the figure, a first suture limb 502 of a suture strand 504 canbe loaded into a retaining mechanism of a suture passing instrument,such as the retaining mechanism 410 disposed at the distal end of thesuture passing instrument 310 described above. In one embodiment, thesuture limb 502 can be loaded by passing the suture limb through theforked distal end 345 of the suture passing instrument 310 and pullingthe suture limb to the proximal end 348 of the suture slot 347. Thefirst suture limb 502 can be loaded such that a tail end 506 extendsfrom a bottom surface of the suture passing instrument. The first suturelimb 502 can be loaded such that the tail end 506 extends from theinstrument by a variety of lengths but, in some embodiments, the tailend 506 can extend from the bottom surface of the suture passinginstrument by about 10-20 mm.

In order to pass a second suture without removing the instrument from apatient's body, a second suture limb 508 can be loaded into theretaining mechanism of the suture passing instrument prior to insertingthe instrument into a patient's body. This can be done, for example, byforming a loop 509 a distance from a tail end 510 of the second suturelimb 508 and threading a portion of the second suture limb 508 into theretaining mechanism 410 in a similar manner as the first suture limb502. As described below in more detail, the loop 509 can be formed at avariety of positions along the length of the suture strand 504 such thatthe second suture limb 508 extends below the suture passing instrumentby a variety of lengths. In some embodiments, the length can be selectedsuch that the tail end 510 of the second suture limb 508 can extendoutside of a cannula or portal when the instrument is inserted into apatient's body, thereby allowing a user to manipulate the second suturelimb 508 during the procedure. In certain embodiments, the length can beselected such that the tail end 510 of the second suture limb 508 canextend from a cannula or portal by at least about 10-20 mm when thesuture passing instrument is inserted into a patient's body. Selectingthe length in this manner can result in the second suture loop 508extending below the suture passing instrument by a greater distance thanthe first suture limb 502, as shown in FIG. 6. By way of example, insome embodiments, the second suture limb 508 can extend below the suturepassing instrument by about 250 mm.

The second suture limb can be, for example, an opposite end of a singlesuture strand 504, as shown in FIG. 5. For example, opposing endportions of a suture strand 504 having a length of about 910 mm can bethe first and second suture limbs 502, 508. In other embodiments,however, the second suture limb can be an end of a second suture strand,as is described in more detail below. Whether using one suture strand ortwo, the suture limbs 502, 508 can, in some embodiments, be selectedfrom the outer two quarters of a suture strand's length, i.e., portionsnot within the middle half of the length of the suture. Selecting thefirst and second suture limbs in this manner can be advantageous as itis possible that the retaining mechanism or other surgical tool coulddamage the suture during a procedure. As a result, the middle portion ofa suture (i.e., the portion that is ultimately left in a patient's bodyto fix tissue) should be handled as little as possible. Handling theouter portions of a suture can be preferable because they can often betrimmed off at the end of a procedure. It should be appreciated that theexemplary lengths described above can be adjusted in view of thisprinciple if, for example, shorter length suture strands are used. Byway of example, the middle portion of a suture strand having an overalllength of about 510 mm (as opposed to, e.g., 910 mm or longer) may bedamaged by a needle or other surgical tool if the second suture limb isloaded as described above (e.g., the tail end 510 extending about 250 mmfrom the lower jaw body 341). To avoid this, the second suture limb 508can be loaded such that the tail end 510 extends below the lower jawbody 341 by a lesser amount in such an embodiment.

As shown in FIG. 6 and mentioned above, the second suture limb 508 canbe loaded into the retaining mechanism 410 of the suture passinginstrument in the same manner as the first suture limb 502, e.g., suchthat the suture limb 508 is received within the suture slot 347 of theretaining mechanism 410 and a tail end 510 of the suture limb 508extends from the bottom surface of the lower jaw body 341 of the suturepassing instrument. However, the second suture limb 508 can be loadedsuch that the second suture limb is seated within the suture slot 347just distally of the first suture limb 502 that is at the proximal-mostend 348 of the slot 347. Also visible in FIG. 6 is the relativedifference in lengths between the portions of the first suture limb 502and the second suture limb 508 extending below the lower jaw body 341 ofthe suture passing instrument. As shown in the figure, the tail end 510of the second suture limb 508 can extend from the suture passinginstrument by a greater distance than the tail end 506 of the firstsuture limb 502. As described above, the length of the second suturelimb 508 can be selected such that the tail end 506 can extend beyondthe proximal end of a cannula or portal when the suture passinginstrument is inserted into a patient's body. In addition, a middleportion 512 of the suture strand 504 can make a loop extending from atop surface of the lower jaw of the suture passing instrument.

An alternative view of the loading orientation of FIG. 6 is shown in thetop view illustration of FIG. 7. As described above, the first suturelimb 502 can be loaded into the suture passing instrument such that itresides at a proximal end 348 of a suture slot 347 that forms theretaining mechanism 410 of the instrument. The second suture limb 508can be loaded into the instrument such that it resides at a locationjust distal to the first suture limb 502. Also visible in FIG. 7 are themovable jaw 350 (shown in an open configuration) and the bendable needle400 residing in the needle channel 343. The needle 400 can include aramp 406 positioned just distal to the notch 405 such that at least theproximal-most suture limb loaded in the retaining mechanism is capturedwithin the notch as the needle 400 is advanced distally through theneedle channel 343.

The extra length of the second suture limb 508 extending from the suturepassing instrument can be utilized in two manners. First, the length ofthe second suture limb 508 extending below the suture passing instrumentcan be used to readily distinguish between the first and second suturelimbs. In addition, the extended length of the second suture limb 508can be utilized to remotely reload the suture passing instrument afterpassing the first suture limb 502 through tissue. For this reason, thesecond suture limb 508 can be pulled toward the proximal end of thesuture passing instrument prior to inserting the instrument into apatient's body, as shown in FIG. 8. In some embodiments, the length ofthe second suture limb 508 can be selected such that the tail end 510remains outside the patient's body (e.g., outside a proximal end of acannula or percutaneous portal used to introduce the instrument into apatient's body) after the suture passing instrument is inserted into thepatient's body, allowing it to be easily manipulated by a user. In someembodiments, the length of the second suture limb 508 can be selectedsuch that at least about 10-20 mm of the second suture limb extendsoutside a patient's body when the instrument is inserted into thepatient's body. Having at least this amount of the second suture limb508 extend outside the patient's body during a procedure can allow auser to easily handle the second suture limb 508 by, for example,pressing the second suture limb against a handle assembly 320 of thesuture passing instrument during use.

In certain embodiments, it can be desirable to maintain tension on thesecond suture limb 508 through portions of the procedure. In particular,it can be desirable to maintain tension on the second suture limbthroughout the procedure, except when deploying the needle to pass asuture through tissue. Maintaining tension on the second suture limb 508can, for example, prevent the second suture limb from becoming entangledwith the loop formed by the middle portion 512 of the suture strand 504.In addition, maintaining tension on the second suture limb 508 canremove any slack and prevent the second suture limb from falling out ofthe retaining mechanism 410 prior to and after deployment of the needle(e.g., when repositioning of the instrument, etc.). To maintain tensionon the second suture limb 508, and to keep the second suture limb easyto access when necessary, the second suture limb can be secured outsidethe patient's body during a procedure. This can be accomplished in avariety of manners, including, for example, by pressing the secondsuture limb 508 against the handle assembly 320 of the suture passinginstrument to maintain its position (e.g., with a finger while using theinstrument). In certain embodiments, a feature can be provided on thehandle assembly 320 or the elongate shaft 330 that allows a user toaffix the second suture limb 508 to the suture passing instrument suchthat the tail end 510 remains accessible throughout a procedure.Exemplary features include a protrusion, eye, or other tie-off. In otherembodiments, the second suture limb 508 can be secured to another deviceoutside the patient's body, such as an access port or other feature on acannula, etc. In still other embodiments, a suture passing instrumentcan be provided with a tensioning wheel or other spring-loadedtensioning mechanism that can pull the second suture limb 508 toward theproximal end of the suture passing instrument when desired. Such adevice can be placed at any location proximal to the retaining mechanismat the distal end of the instrument and, if capable of applyingsufficient tension to the second suture limb 508, need not be at alocation that remains outside the patient's body.

After loading the first and second suture limbs 502, 508 into theretaining mechanism 410 of the suture passing instrument 310, the jaws314 can be closed to lower the profile of the suture passing instrumentand the instrument can be inserted into a patient's body. The instrumentcan be inserted into the body using any known method for introducingsurgical tools. In some embodiments, as shown in FIG. 9, the instrument310 can be inserted into the patient's body through a cannula 902. Inaddition, the instrument can be positioned within a patient's body at avariety of sites. In the embodiment illustrated in FIG. 9, theinstrument is shown positioned near a patient's shoulder to pass suturesthrough the muscle and tendon that form the patient's rotator cuff. Alsovisible in FIG. 9 is the second suture limb 508 and the loop formed bythe middle portion 512 of the suture strand 504 extending back out ofthe cannula 902.

Although cannulas are often used to define a channel through which theprocedure can be performed, the cannula is not shown in FIGS. 10-13, 15,and 16 for ease of illustration. Accordingly, to the extent that thefigures show components that pass through a patient's skin, thesecomponents would typically extend through a cannula, which itself can bepassed through the patient's skin. Furthermore, certain embodiments of asuture passing instrument can be inserted into a patient's body througha percutaneous insertion portal (e.g., an opening formed in the tissueusing an obturator). The methods described herein can be particularlysuited to use through such a portal or opening formed in the skinbecause they can avoid problems encountered with prior art suturingmethods. For example, prior art suturing methods can create a problemknown as “bridging” if a suture passing instrument finds a slightlydifferent path through a patient's skin and tissue when reinserted topass a second suture (i.e., the suture can trap the tissue between thetwo entry paths). The methods described herein can avoid bridging tissuebecause the suture passing instrument need not be removed betweenconsecutive suture passes. Still further, although the methods describedherein are particularly useful for minimally invasive surgery, such asarthroscopic surgery, they can also be used in open surgical procedures.

Once the suture passing instrument 310 is introduced into the patient'sbody through a cannula or other mechanism, the movable jaw 350 can beopened and the instrument can be positioned such that tissue is disposedbetween the jaws 314. In some embodiments, the second suture limb 508can be tensioned at this time to remove any slack that may have formedand ensure that the second suture limb 508 is seated in a proximalportion of the retaining mechanism adjacent to the first suture limb502. A user can then actuate the jaw movement mechanism 360 to closemovable jaw 350, thereby clamping tissue between the movable jaw 350 andthe lower jaw 340.

The needle movement mechanism 380 can then be actuated to deploy thebendable needle from the distal end of the suture passing instrument 310and carry a portion of at least the first suture limb 502 through thetissue grasped between the jaws 314. As noted above, any tension on thesecond suture limb 508 can be released prior to actuating the needlemovement mechanism 380, thereby allowing the needle to deploy withoutencountering resistance. FIG. 10 illustrates a suture passing instrument310 with a needle 400 in a deployed position. In this configuration, theneedle 400 extends out of the channel exit 344 on the lower jaw 340 (notshown), through the tissue 1000, and through the opening 355 formed inthe movable jaw 350. As shown in the figure, the notch 405 of thebendable needle 400 can carry portions of both the first and secondsuture limbs 502, 508 through the tissue such that the tail ends of thefirst and second suture limbs 506, 510 extend from a first surface 1002of the tissue 1000 and first and second suture loops 1006, 1008 areformed on a second surface 1004 of the tissue 1000 that is opposite fromthe first surface 1002. The needle 400 may not always carry both suturelimbs 502, 508 through the tissue, so in some embodiments only a singlesuture loop 1006 may be formed on second surface 1004 of the tissue1000, as shown in FIG. 13.

Following deployment, the needle can be retracted into the suturepassing instrument 310. The notch 405 can be configured to carry thefirst and/or second suture limbs 502, 508 only when being extended suchthat retracting the needle 400 can leave the first and second sutureloops 1006, 1008 undisturbed, as shown in FIG. 11. Also visible in FIG.11 is the second suture limb 508 extending toward a proximal end of thesuture passing instrument, and the large loop formed by the middleportion 512 of the suture strand 504. As mentioned above, the middleportion 512 can hang freely or can extend toward the proximal end of thesuture passing instrument with the second suture limb 508. In someembodiments, the middle portion 512 can be long enough that it extendsthrough the cannula used to introduce the suture passing instrument 310and outside of the patient's body.

After the needle is retracted, it is possible that two substantiallyequally-sized suture loops 1006, 1008 are formed on the second surface1004 of the tissue 1000. However, it is also possible that one sutureloop is larger than the other, or that only a single suture loop isformed on the second surface 1004. If only a single suture loop isformed on the second surface, as shown in FIG. 13, the needle carriedonly the first suture limb 502 through the tissue. In such a case,tension is applied to the second suture limb 508 (to prevent it frombeing pulled through with the first suture limb) and a grasper tool canbe used to grasp the suture loop and pull it until the tail end 506 ofthe first suture limb 502 comes through the tissue. FIG. 14 illustratesone embodiment of a grasper tool 1402 being inserted into a patient'sbody using a second cannula 1404 and grasping a first suture loop 1006.Once the suture loop is grasped, the grasper tool 1402 can be withdrawnfrom the patient's body to pull the first suture limb 502 through thetissue, as shown in FIG. 15. In some embodiments, the first suture limb502 can be drawn through an ancillary portal (e.g., second cannula 1404)outside of the patient's body for ease of suture management. In otherembodiments, the hook feature 1010 of the upper jaw 350 can be utilizedin place of a grasper tool to draw the first suture limb 502 through thetissue 1000.

If two suture loops are present, as shown in FIG. 11, the method caninclude determining which of the two suture loops 1006, 1008 correspondsto the first suture limb 502 by pulling the second suture limb 508toward a proximal end of the suture passing instrument, as shown by thearrow in FIG. 12. Pulling on the second suture limb 508 draws the secondsuture limb in a proximal direction and reduces the size of the secondsuture loop 1008 formed on the second surface 1004 of the tissue 1000.The second suture limb 508 can be pulled until the second suture loop508 retracts through the tissue 1000 completely, leaving the firstsuture loop 1006 alone, as shown in FIG. 13. A suture grasper or othertool can then be inserted as described above and used to pull the firstsuture loop 1006 until the tail end 506 of the first suture limb 502passes through the tissue 1000. If the first suture limb 502 is pulledfurther, the middle portion 512 of the suture strand 504 can begin topass through the tissue, thereby shortening the size of the loop formedby the middle portion 512 of the suture strand, as shown in FIG. 15. Insome embodiments, the first suture limb 502 can be pulled far enoughthat the middle portion 512 of the suture strand 504 is contained withina cannula used to introduce the instrument and does not extend outsidethe body before proceeding to pass a second suture through tissue.

After passing the first suture limb 502 through the tissue 1000, thesuture passing instrument can be remotely reloaded without removing thedevice from the patient's body. To reload, the second suture limb 508can be pulled toward a proximal end of the suture passing instrumentsuch that the second suture limb 508 is moved proximally within theretaining mechanism 410 of the instrument, as shown by the arrow in FIG.16. In other words, the second suture limb 508 can be pulled proximallysuch that it resides in the proximal end 348 of the suture slot 347 thatwas previously occupied by the first suture limb 502. In addition, thesuture passing instrument 310 can be repositioned at this time to passthe second suture limb 508 through tissue 1000 at a different locationthan the first suture limb 502. This can be accomplished by opening thejaws 314 and moving the suture passing instrument from a first location1602 to a second location 1604, while simultaneously keeping a lighttension on the second suture limb 508 to prevent it from falling out ofthe suture slot 347. Alternatively, the suture passing instrument neednot be repositioned and the second suture limb 508 can be passed throughthe tissue at the same location as the first suture limb 502, therebyreducing the number of holes formed in the tissue. Regardless of whetheror not the suture passing instrument is repositioned, in someembodiments the jaws 314 can be at least partially opened to remove anyresistance to the movement of the second suture limb 508 and reduce thepossibility of the jaws 314 damaging the suture strand 504. For example,in some embodiments, the jaws can be opened a small amount to allow thesecond suture limb 508 to move without resistance while preventing therepositioning of the suture passing instrument with respect to thetissue.

Passing the second suture limb 508 after remotely reloading the suturepassing instrument involves repeating the steps detailed above fordeploying the needle, retracting the needle, and grasping a suture loopformed on the second surface 1004 of the tissue 1000 to draw the tailend 510 of the second suture limb 508 through the tissue, as shown inFIGS. 10 and 13-15. However, in some embodiments, a different tool canbe used to grasp the suture loop and draw the second suture limb 508through the tissue 1000. In particular, in some embodiments a loopingdevice or other suture manipulator configured to allow the second suturelimb 508 to slide across the manipulator can be utilized in place of agrasper configured to rigidly grip the second suture limb. Such a devicecan be preferable because, in the case of the second suture limb 508,there can be a large amount of suture that must be pulled through thetissue 1000 before the tail end 510 of the second suture limb 508 passesthrough the tissue (i.e., the extra length of the second suture limb 508extending outside of the patient's body must be drawn into the patient'sbody and through the tissue). Using a grasper that does not slide alongthe suture strand to draw this extra length through the tissue cansimultaneously pull the first suture limb 502 back into the patient'sbody through the ancillary portal (e.g., second cannula 1404). Bycontrast, if a looping device or other sliding suture manipulator isused, the first suture limb 502 can be secured outside the body (e.g.,by holding the suture or even by the friction from the second cannula'sseals) such that it is not drawn back into the patient's body. Inaddition, before pulling the suture loop to draw the second suture limb508 through the tissue, any tension maintained on the second suture limb508 can be released to allow the second suture limb 508 to be pulledinto the patient's body and through the tissue.

If the first and second suture limbs 502, 508 are opposite ends of asingle suture strand 504, as shown in FIGS. 5-16, the end result will bean inverted mattress stitch formed in the tissue 1000. FIG. 17Aillustrates two inverted mattress stitches 1702, 1704 formedside-by-side in tissue 1700. The mattress stitch 1702 is formed bypassing opposing ends 1706, 1708 through the tissue from an undersidethereof at different locations. This leaves the opposing ends 1706, 1708free on a top surface of the tissue 1700, and a middle portion 1710connecting the ends on a bottom surface of the tissue (shown inphantom). The second inverted mattress stitch 1704 is formed in asimilar manner.

The methods described herein can also be utilized to form a number ofother stitching patterns. For example, it is possible that theorientation of the suture passing instrument can be reversed to form atraditional mattress stitch (i.e., the tail ends of the suture strandextend below the tissue with a middle portion connecting them on a topsurface of the tissue). However, in many cases this is not possible dueto space constraints on the underside of the tissue. For example, in arotator cuff repair procedure, the muscle and tendon of the rotator cufflies against the underlying bone. Deploying a needle from the suturepassing instrument so as to create a mattress stitch can result ininjury to the bone from contact with the needle tip. This could beachieved, however, with a shorter length needle (e.g., a needle thatdoes not extend as far from the suture passing instrument when in thefully deployed state). The methods described herein can also be used informing a number of variations on the mattress stitch, such as aninclined mattress stitch and a Mason-Allen stitch.

In other embodiments, the suture passing instrument can be loaded withsuture limbs from two separate suture strands. This configuration can beused, for example, to form a double-width inverted mattress stitch, asshown in FIG. 17B. The double-width inverted mattress stitch 1720 can beformed by passing first suture limbs 1722, 1724 from two separate suturestrands through tissue 1700 at a first location. The suture passinginstrument can then be removed from the patient's body and loaded asdescribed above with second suture limbs 1726, 1728 that are theopposite ends of the two separate suture strands. The suture passinginstrument can be reintroduced into a patient's body and the secondsuture limbs 1726, 1728 can be passed through the tissue 1700 at asecond location using the methods described above. In such anembodiment, the need to remove and reintroduce the suture passinginstrument into the patient's body is not eliminated entirely, but isreduced significantly to minimize the complexity and time required toform this type of stitch.

The methods described herein can be utilized in a number of differentsurgical procedures at a variety of locations within a patient's body.In one embodiment, the methods can be utilized in repairing a rotatorcuff tear in a patient's shoulder. FIGS. 18A-18D illustrate oneembodiment of a “spanning technique” method for repairing a rotator cufftear utilizing the suture passing methods described herein. FIG. 18Ashows a patient's humerus 1802 and scapula 1804, along with the muscleand tendon that form the rotator cuff 1806. A tear 1808 is present inthe muscle and/or tendon 1806. To repair the tear and fix the muscle tothe humerus 1802, medial anchors 1810, 1812 can be used to secure twosuture strands 1814, 1816 to the humerus, thereby creating four freeends of suture that are anchored to bone. In some embodiments, however,only a single medial anchor (e.g., anchor 1810) can be used. The fourfree ends of the two suture strands 1814, 1816 can be passed through themuscle and tendon of the rotator cuff 1806 using the methods describedherein. For example, the two free ends of the suture 1814 can be loadedas the first and second suture limbs 502, 508 and passed through thetissue 1806 in one location, and then the method can be repeated usingthe two free ends of the suture 1816, as shown in FIG. 18C. In someembodiments, however, the two free ends of the suture 1814 can be passedthrough tissue in different locations (e.g., at two locations spacedapart by 4-6 mm). In such an embodiment, the same process can berepeated for two free ends of the suture 1816.

The four free ends of the two suture strands 1814, 1816 can then bemanipulated to move the rotator cuff muscle and tendon 1806 into adesired location. The free ends of the suture strands can be “spanned”across and secured to a second set of anchors 1818, 1820 in a number ofmanners known in the art, as shown in FIG. 18D. Of course, this is justone embodiment of a possible method for repairing a rotator cuff tear.In other embodiments, the tear can be repaired using one or moreinverted mattress stitches, double-width inverted mattress stitches, orMason-Allen stitches.

All papers and publications cited herein are hereby incorporated byreference in their entirety. One skilled in the art will appreciatefurther features and advantages of the invention based on theabove-described embodiments. Accordingly, the invention is not to belimited by what has been particularly shown and described, except asindicated by the appended claims.

What is claimed is:
 1. A method of passing a suture through tissue,comprising: loading a first suture limb into a retaining mechanismdisposed at a distal end of a suture passing instrument such that thefirst suture limb extends on a first side of the instrument; loading asecond suture limb into the retaining mechanism of the suture passinginstrument such that the second suture limb extends on the first side ofthe instrument; positioning first and second jaws of the suture passinginstrument to grasp tissue within a patient's body; deploying a needlefrom the suture passing instrument such that the needle extends throughthe tissue grasped between the first and second jaws of the instrument,the needle carrying a portion of at least the first suture limb throughthe tissue such that the first and second suture limbs extend from afirst tissue surface and at least a first suture loop is formed on asecond tissue surface opposite the first tissue surface; pulling thefirst suture loop to draw the first suture limb through the tissue;pulling the second suture limb toward a proximal end of the suturepassing instrument to draw the second suture limb into a proximal end ofthe retaining mechanism without removing the suture passing instrumentfrom the patient's body; deploying the needle from the suture passinginstrument a second time to carry a portion of the second suture limbthrough the tissue such that the second suture limb extends from thefirst tissue surface and a second suture loop is formed on the secondtissue surface; and pulling the second suture loop to draw the secondsuture limb through the tissue.
 2. The method recited in claim 1,wherein the second suture limb extends farther from the suture passinginstrument than the first suture limb.
 3. The method recited in claim 1,wherein the first suture limb extends from the suture passing instrumentby about 10-20 mm.
 4. The method recited in claim 1, wherein the secondsuture limb extends from the suture passing instrument by about 250 mm.5. The method recited in claim 1, wherein positioning the first andsecond jaws of the suture passing instrument comprises inserting theinstrument into a patient's body, opening the jaws to receive tissuetherebetween, and closing the jaws to grasp the tissue.
 6. The methodrecited in claim 5, wherein the instrument is inserted into thepatient's body through a cannula.
 7. The method recited in claim 1,further comprising retracting the needle following deployment such thatthe needle retracts into the suture passing instrument without movingthe first or second suture limbs.
 8. The method recited in claim 1,further comprising, prior to pulling the first suture loop, determiningwhich of two suture loops is the first suture loop by pulling the secondsuture limb toward a proximal end of the suture passing instrument toreduce the size of a second suture loop formed on the second tissuesurface.
 9. The method recited in claim 1, further comprising at leastpartially opening the first and second jaws prior to pulling the secondsuture limb toward a proximal end of the instrument to permit easiermovement of the second suture limb with respect to the retainingmechanism.
 10. The method recited in claim 1, further comprisingrepositioning the suture passing instrument without removing theinstrument from the patient's body before deploying the needle a secondtime such that the second suture limb is passed through tissue at adifferent location than the first suture limb.
 11. The method recited inclaim 10, wherein repositioning the suture passing instrument comprisesopening the first and second jaws to release the tissue graspedtherebetween, moving the instrument to receive a different portion oftissue between the first and second jaws, and closing the first andsecond jaws to grasp the different portion of tissue therebetween. 12.The method recited in claim 1, wherein the suture passing instrument isnot repositioned between the first and second deployments of the needlesuch that both the first and second suture limbs extend through a singlehole formed in the tissue.
 13. The method recited in claim 1, furthercomprising attaching the second suture limb to a tensioning devicecoupled to the suture passing instrument at a location proximal to theretaining mechanism, the tensioning device being configured to pull thesecond suture limb toward a proximal end of the instrument.
 14. Themethod recited in claim 1, further comprising attaching the first andsecond suture limbs to a bone anchor.
 15. The method recited in claim 1,wherein the first and second suture limbs are opposite ends of a singlesuture strand.
 16. The method recited in claim 1, wherein the first andsecond suture limbs are ends of separate suture strands, the methodfurther comprising repeating the steps recited in claim 1 using theopposite ends of the separate suture strands as the first and secondsuture limbs.
 17. A method of passing a suture through tissue,comprising: loading first and second suture limbs into a retainingmechanism of a suture passing instrument such that the first and secondsuture limbs extend from a first side of the instrument; inserting thesuture passing instrument into the body of a patient; positioning firstand second jaws of the suture passing instrument to grasp tissuetherebetween; actuating the suture passing instrument to pass a portionof at least the first suture limb through the tissue grasped between thefirst and second jaws such that the first and second suture limbs extendfrom a first tissue surface and at least a first suture loop is formedon a second, opposite tissue surface; pulling the first suture loop todraw the first suture limb through the tissue; pulling the second suturelimb toward a proximal end of the suture passing instrument to draw thesecond suture limb into a proximal end of the retaining mechanismwithout removing the suture passing instrument from the patient's body;actuating the suture passing instrument a second time to pass a portionof the second suture limb through the tissue grasped between the firstand second jaws such that the second suture limb extends from the firsttissue surface and a second suture loop is formed on the second tissuesurface; and pulling on the second suture loop to draw the second suturelimb through the tissue.
 18. The method recited in claim 17, furthercomprising, prior to pulling the first suture loop, determining which oftwo suture loops is the first suture loop by pulling the second suturelimb toward a proximal end of the suture passing instrument to reducethe size of a second suture loop formed on the second tissue surface.19. The method recited in claim 17, further comprising repositioning thesuture passing instrument without removing the instrument from thepatient's body before actuating the instrument a second time such thatthe second suture limb is passed through tissue at a different locationthan the first suture limb.
 20. The method recited in claim 17, whereinthe first and second suture limbs are ends of separate suture strands,the method further comprising removing the instrument from the patient'sbody and repeating the steps recited in claim 16 using the opposite endsof the separate suture strands as the first and second suture limbs. 21.A method for repairing a tear in tissue, comprising: loading a firstsuture limb into a retaining mechanism disposed at a distal end of asuture passing instrument, the first suture limb having a free end andan opposite end anchored to bone within a patient's body; loading asecond suture limb into the retaining mechanism of the suture passinginstrument, the second suture limb having a free end and an opposite endanchored to bone within a patient's body; positioning first and secondjaws of the suture passing instrument to grasp tissue within thepatient's body; actuating the suture passing instrument to pass aportion of the first suture limb through the tissue grasped between thefirst and second jaws such that a first suture loop is formed on asurface of the tissue; pulling the first suture loop to draw the freeend of the first suture limb through the tissue; pulling the free end ofthe second suture limb toward a proximal end of the suture passinginstrument to draw the second suture limb into a proximal end of theretaining mechanism without removing the suture passing instrument fromthe patient's body; actuating the suture passing instrument a secondtime to pass a portion of the second suture limb through the tissuegrasped between the first and second jaws such that a second suture loopis formed on the surface of the tissue; pulling on the second sutureloop to draw the free end of the second suture limb through the tissue;and anchoring the free ends of the first and second suture limbs to boneto secure the tissue with respect to the bone.
 22. The method of claim21, wherein anchoring the free ends of the first and second suture limbsto bone comprises securing the free end of the first suture limb to afirst bone anchor and the free end of the second suture limb to a secondbone anchor.
 23. The method of claim 21, further comprisingrepositioning the suture passing instrument prior to actuating thesuture passing instrument a second time.